A general box making machine for corrugated cardboard sheets produces corrugated cardboard boxes by processing a corrugated cardboard sheet in which a corrugating medium is adhered between a pair of liners, and includes a sheet feeding unit, a printing device, a slotter/creaser, a folding unit, and a counter ejector.
According to the sheet feeding unit, a kicker that is operated by a crank lever kicks out corrugated cardboard sheets stacked on a table, feed rolls sandwich the corrugated cardboard sheets at a constant speed, and feed them to the printing device.
The printing device performs printing in a single color or multiple colors, and includes one or more printing units. Each of the printing units includes a printing cylinder, and a printing plate is mounted on the cylinder. An ink supply roll that is abutted against the printing plate is provided near the printing cylinder, and an ink chamber that stores printing ink is provided near the ink supply roll. Ink is supplied on a surface of the ink supply roll from the ink chamber, and the ink is transferred to the printing plate. A receiving roll is provided below the printing cylinder, and printing is performed in a state that the corrugated cardboard sheet is sandwiched between the printing plate and the receiving roll.
The slotter/creaser draws a creasing on a printed corrugated cardboard sheet by first and second creasing rolls, and cuts a slot in the creased corrugated cardboard sheet by a slotter knife.
A folding unit applies an adhesive to a sticking tab piece by an adhering device while moving the corrugated cardboard sheet. The corrugated cardboard sheet to which the adhesive is applied is continuously moved and in this state, a folding bar and a folding belt fold the sheet, and the sticking tab piece is adhered, thereby producing a corrugated cardboard box. The corrugated cardboard sheets are folded and adhered and the corrugated cardboard boxes are formed, and the counter ejector stacks these boxes by a hopper, sorts these boxes into batches with a predetermined number of boxes, and then discharges the batch of the predetermined number of the boxes.
According to the box making machine for corrugated cardboard sheets having such a configuration, in the printing device, ink is supplied on a surface of the ink supply roll from the ink chamber, and when the ink supply roll rotates, ink is transferred onto a surface of the printing plate of the printing cylinder that is opposed and in contact with the ink supply roll, the corrugated cardboard sheet is conveyed between the printing plate and the receiving roll, and then printing is performed on the surface of the corrugated cardboard sheet.    Patent Documents 1 and 2 mentioned below disclose such a printer for corrugated cardboard sheets.    Patent Document 1: Japanese Patent No. 2974100    Patent Document 2: Japanese Utility Model Registration No. 2602428